100YSS: SETI, Sprites and Cutting Costs

byPaul GilsteronSeptember 23, 2014

Gatherings like the 100 Year Starship Symposium have tough organizational choices to make, and the solutions aren’t always obvious. A good part of any aerospace conference is involved in presenting papers, but do you set up a multi-track system or take a single-track approach? In Houston, the 100 Year Starship organization chose multiple tracks: We had, for example, a track on Life Sciences, one on Data Communications, another on Propulsion & Energy, and there were several others including a useful track on Interstellar Education.

The problem is that with all these tracks running at once, it was a matter of picking and choosing, and that often meant getting up after a presentation, switching rooms, and entering another track. I missed papers in Kathleen Toerpe’s Education track that I wanted to hear because I needed to hear many of the Propulsion & Energy papers, and while I caught a paper in the Becoming an Interstellar Civilization track, it was at the expense of some promising offerings in another track called Uncharted Space & Destinations.

This is how many conferences operate and it allows for a greater number of papers, but I was glad that the symposium also opened up for plenary sessions, one of which, called State of the Universe, was a discussion between Jill Tarter (SETI Institute) and Mason Peck (Cornell University). Tarter’s lengthy involvement in SETI brings particular weight to her insights, and Centauri Dreams readers already know about my admiration for Peck’s work on the miniaturized ‘satellite on a chip’ designs he and his team call ‘Sprites.’ I’m convinced that shrinking payloads through such technologies is a promising path toward interstellar missions.

Miniaturization and Cost

KickSat was a plan to take a large number of Sprites into orbit aboard a CubeSat, although the initial attempt failed when, after a launch in April of this year as part of an ISS re-supply mission, the CubeSat orbited and re-entered without deploying the nanosatellites. But the technology is fascinating. Peck refers to Sprites as ‘Sputnik on a microchip,’ and we can think of them as robotic precursor missions on a very small scale, an economic approach to exploration. A swarm of cheap Sprites could be deployed, for example, from a CubeSat solar sail mission to an outer planet, replacing telescope imagery with direct sensor readings.

But Tarter pressed Peck on astrobiology, where for our immediate purposes, Sprites aren’t going to offer the flexibility of today’s large rovers on places like Mars. How do we cope with the need to keep the costs of large missions down? The commercial sector, as well as crowdsourced funding, came up again and again. In Peck’s words:

“For Mars, the long range plan is a sample return mission. To keep the prices as low as possible, what if we buy the science? Rather than having an agency declare the boundaries of a science mission, why not offer a prize per gram of Martian soil? Let companies bid and bring economics into play. If no one rises to the challenge, no money is spent.”

Tarter was interested in what she called a ‘mega-Kickstarter from the world’ as a funding source for another kind of technology, a starshade. In reports for the NASA Institute for Advanced Concepts a few years back (still available at the NIAC site), Webster Cash (University of Colorado at Boulder) outlined the possibilities. Even the largest planets are invariably drowned out by the glare of the parent star, but a starshade approximately 20,000 kilometers away from a large space instrument like the James Webb Space Telescope uses a highly-refined ‘flower-petal’ architecture to filter out the starlight, leaving the telescope with photons from the exoplanet itself. That makes spectroscopy possible, allowing us to study the constituents of a planetary atmosphere.

Starshades are big and have to be deployed, which led Tarter to her next question: Given the kind of miniaturized technology Peck was already working with, couldn’t we make a starshade out of a swarm of smaller objects? The problems are daunting, and include keeping the surface of these structures precise enough to prevent problems with diffraction that can cloud the image. Even so, Peck noted the radical change that computation has brought to optics in the last few years, offering hope of dealing with the optics of widely distributed systems.

And I love this idea: We have places in the Solar System like Enceladus, Europa and Triton, where cryovolcanoes are known to exist. What Tarter calls a ‘shortcut to a sample return’ is to fly a swarm of Sprites through material these cryovolcanoes are throwing into space. Peck’s response:

“I don’t see why not. Small sensors could be distributed throughout this environment. If you fly hundreds — or millions — of Sprites through a geyser, you hedge your bets for survival. Even better, you get spatially and temporally distributed sets of measurements that make a different kind of science possible. It’s a ‘village’ of satellites rather than a single big spacecraft that has to work or you lose the mission. A swarm offers a stochastic or random look at the target.”

The Assumptions of SETI

When the conversation turned to SETI, Tarter talked about current work in the radio and optical part of the spectrum and the need to move to larger apertures and greater computing power, noting that SETI would be part of the Square Kilometer Array that will go online in the 2023-2025 timeframe. In optical wavelengths, the coming generation of instruments like the European Extremely Large Telescope and the Thirty Meter Telescope might have places in the focal plane where SETI detectors could be deployed.

Peck wanted to know whether the assumption was that other civilizations are trying to contact us, or would it be possible to pick up accidental transmissions. Tarter’s response:

“We assume most of the gain is in the transmitter, so receivers don’t need to be as powerful. But in the case of other kinds of signals, those that are not deliberate — think of large astro-engineering programs, for example — any leakage is going to be extremely weak. For these we would have to build the gain into the receivers. But putting huge amounts of money into a single area doesn’t seem the right way to go. Better to do more small but different things. For now, the philosophy is to go for deliberate signals and try to be affordable.”

Driving the push into optical wavelengths has been our own experience. Peck likens the way we currently communicate and return data from spacecraft to ‘exploring the universe with a dial-up modem.’ We have low communications bandwidth and leave about 85 percent of the images we collect on Mars. Improving communications by a factor of ten through laser methods would allow far greater science return. And if we find lasers valuable, wouldn’t other civilizations come to the same conclusion? A large aperture doing individual photon counting can detect a very distant signal.

I liked the note the session ended on, the idea that working on a distant goal like a starship can have wide impact on Earth in the near future. Tarter noted that we’re going to have a large number of megacities before long, teeming with populations of 20 million or more each. Everything we need to learn about maintaining stable life support systems for a starship flows as well into how to keep such cities alive and healthy. Cities as starships. We don’t always plan the solutions that work, but experience has shown how often they emerge from pushing into the unknown.

Comments on this entry are closed.

MattSeptember 23, 2014, 14:21

I found the State of the Universe session particularly inspiring. I am a definitely a Mason Peck fan. I hope the idea of trying smaller spacecraft takes off. We will learn a lot faster if we do experiments with short lead time and quicker feedback.

Great stuff Paul. NASA have announced a public competition with a $20K prize for reducing spacecraft weight to Mars in order to increase payload. Perhaps they are listening. All down to propellant, or lack of it as any interstellar starship designer knows I suspect. Or shrinking as suggested above.
Interesting the comments about computing power maximising optics and the Square Kilometre Array. I was at Jodrell Bank telescope the other day, who have been appointed as the administration lead for the SKA, and they told me there isn’t a powerful enough computer built yet that could cope with the SKA’s processing needs. But thanks to the speed of progress, Moores Law and all, they are not worried about one being available come the launch in ten years ( and a 32 times processing improvement).

I have a great deal of time for Richard Dawkins so thanks for the link (‘Through the Wormhole’ recently covered the alien religion thing which was ok for the most part and loosely in tune with my own bias on the matter… namely intelligences going through the religion phase is probably common and useful for establishing working societies that have an evolutionary advantage; one that becomes a disadvantage once the species becomes powerful enough to a) destroy itself so easily, and b) take the reigns from nature in deciding its own evolution, effectively removing natural selection, as we have been doing since the advent of modern medicine).

I chatted with Jill Tarter at Astrofest a couple of years ago and she struck me as a very nice person (story would be better if it ended at “struck me”)

Religions/world views evolve alongside the societal implications of humanity and may not necessarily disappear, but become syncretic with whatever situations are at hand, including those of self-destruction, artificial selection and genetic engineering. If there are thousand year old religions alive and kicking today, there’ll be million year, even billion year old ones we’ll have to put up with, eventually.

There does seem to be a correlation between modern medicine, a commercial quality of life in “developed” countries, and birthrate decline. But sex isn’t as problematic as Dawkins pretentiously makes it seem. First, there are threemain sexes (not two, by virtue of intersex or “hermaphrodism”) as well as many sub-sexes we label as “genders” and even within gender there can be diversity, mostly labeled as “orientations”. And even on a psychological level, there exists “partialism” and “fetishism” within those complex structures. Altogether, they seems to work without any problems, biologically, and not only for the species engaging in sexual activity. We will more than likely come across this, too, in ET, in varying degrees. In fact, sexuality is extremely practical and it is very much within our capabilities to manipulate the process to aid in, or defer any “problems” artificially, via selection or technology and medicine.

Simply, reproductive pressures and the promotion or suppression of different traits are what will drive (or eliminate/enable) sex.

As for megacities and cities as starships, I think it’d be a mistake not to also learn from those civilizations still untouched by industrialization and urbanization. Of course, these people’s environments are being negatively impacted by oil companies, loggers, drug traffickers, and governments–Are these woes we want to take with us for the long-haul into space? Each one has a simple solution (elimination of: reliance on fossil fuels, over exploitation of resources, criminality/regulation of drugs, assimilation/forced integration policy), but how would we go about honoring these solutions, is it humanly possibly, or will these civilizations also turn into what we have become and we should therefore continue on as usual?

In 1930, Albert Einstein was asked for his opinion about the possibility of life elsewhere in the universe. “Other beings, perhaps, but not men,” he answered. Then he was asked whether science and religion conflict. “Not really, though it depends, of course, on your religious views.”

Over the past 10 years, astronomers’ new ability to detect planets orbiting other stars has taken this question out of the realm of philosophy, as it was for Einstein, and transformed it into something that scientists might soon be able to answer.

Realization that the nature of the debate about life on other worlds is about to fundamentally change led Vanderbilt Professor of Astronomy David Weintraub to begin thinking seriously about the question of how people will react to the discovery of life on other planets.

He realized, as Einstein had observed, that people’s reactions will be heavily influenced by their religious beliefs. So he decided to find out what the world’s major religions have to say about the matter. The result is a book titled “Religions and Extraterrestrial Life” (Springer International Publishing) published this month.

In answer to the question “Are we ready?” Weintraub concludes, “While some of us claim to be ready, a great many of us probably are not… very few among us have spent much time thinking hard about what actual knowledge about extraterrestrial life, whether viruses or single-celled creatures or bipeds piloting intergalactic spaceships, might mean for our personal beliefs [and] our relationships with the divine.”

The year 1970 was a good one for whales — at least when it came to record sales. That year Capitol Records released “Songs of the Humpback Whale,” a series of recordings of humpbacks off the coast of Bermuda, made by a team led by the marine scientist Roger Payne. This was no “Abbey Road” — it featured only the sounds made by the whales, without human accompaniment — but the record became an became an overnight sensation and soon, the best-selling nature recording ever.

It is largely credited with raising public awareness of the plight of whales, making it a cause so emblematic that it is often identified as the birth of the environmental movement — not to mention the source of endless jokes about the post-hippie, stoned-out, early-New Age 1970s.

I myself have never had one of those moments when I looked into the eye of a whale and knew we shared something special — no, nothing like that. My encounters with humpback whales happen mainly through sound. Along with being a philosophy and music professor, I play music for a living: some of my fellow musicians are humans, but just as often they are animals, and sometimes those animals are whales. I sit on a boat, swaying in the waves, headphones on, listening to what goes on below and try to play along.

Music expresses emotions, and that’s why we love it so. Whales and humans may share a capacity to express complex emotions. You see, both our brains contain a mysterious kind of cell called the spindle neuron, that until recently was known only in the brains of primates. We don’t know exactly what it is for, but scientists believe it has something to do with the ability to experience complex, layered emotions. And whales have three times the number of these cells in their brains than we do.

In case you are doubtful about all this I can assure you: whales do really sing, but not always the way you might imagine. There’s much more than high, plaintive cries — there are grunts, squeaks, beats, cool noises that can sound more electronic than melodic, a full range of the kinds of crazy sounds that humans can call music today. Although we think we are always pushing the boundaries of what counts as music, humpback whales have been doing it for millions of years.

Most times when I drop my microphone and speaker underwater to play with the whales, I feel awfully lonely. There I am, making a strange sound and sending it out underwater, just hoping a whale might connect what he sings to what I’m playing. Often they just ignore me, but in the best of moments, and such a moment is just as rare as playing along with human musicians, some real contact may happen.

Other comments:

Thankfully some whale songs were placed on the two Voyager Interstellar Records in 1977 to be preserved for at least one billion years among the stars of the Milky Way galaxy:

It is said that Mahatma Gandhi, when asked about Western civilization, remarked, “I think it would be a good idea.” That’s how I feel about intelligent life on Earth, especially when I think about the question of what truly intelligent life might look like elsewhere in the universe.

What do we mean by intelligence? Like life, it’s hard to define, but we need to if we want to search for it. Among the radio astronomers of SETI—the Search for Extraterrestrial Intelligence—it’s only sort-of a joke that the true hallmark of intelligent life is the creation of radio astronomy.

Modern SETI was born as the Cold War simmered. In late 1959 Giuseppe Cocconi and Philip Morrison published, in Nature, calculations showing that radio telescopes could transmit signals across interstellar distances. In 1960 Frank Drake decided to search, using the Green Bank Radio Observatory in West Virginia.

He also led a workshop there, which produced the famous “Drake equation” for determining the number of broadcasting civilizations by taking into account the number of stars, the number of stars likely to have planets, etc. It was never meant to calculate a specific answer so much as to frame the discussion about how development of planets, life, and civilizations could affect the likelihood of finding anyone out there to talk to.

Great to hear that the SKA telescope was mentioned as indeed, SETI is one of its proposed observation programs! Fun fact: the SKA will be powerful enough to detect the equivalent of an airport radar on a planet dozens of light years away! Perhaps Centauri Dreams could dedicate an article to it? If so let me know!

In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For the last eleven years, this site has coordinated its efforts with the Tau Zero Foundation, and now serves as the Foundation's news forum. In the logo above, the leftmost star is Alpha Centauri, a triple system closer than any other star, and a primary target for early interstellar probes. To its right is Beta Centauri (not a part of the Alpha Centauri system), with Beta, Gamma, Delta and Epsilon Crucis, stars in the Southern Cross, visible at the far right (image: Marco Lorenzi).

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